Such modules are used in a robot of the elephant trunk or snake type. This type of robot is for example used to reproduce the movement of a vertebral column.
The human vertebral column is that part of the human body having the greatest number of articulations. Each of these articulations has five to six degrees of freedom. Numerous attempts have been made, in humanoid robots, to come as close as possible to human functionality.
Conventional attempts have focused on reproducing, in robots, multiple vertebrae of human a vertebral column by arranging motorized articulations between each vertebra. In order to come close to a human vertebral column, it is necessary to provide a large number of articulated vertebrae.
Conventionally, the vertebrae of robots are formed by plates, and actuators perpendicular to the plates serve as articulations between the vertebrae. The amplitude of movement of the actuators contributes to the mobility of the vertebral column. This amplitude is limited by the distance between two adjacent plates. In a given space, increasing the number of vertebrae can only be made by sacrificing the amplitude of relative movement between the vertebrae.